With the world's supply of petroleum diminishing, much emphasis has been placed on finding substitutes for fuels such as gasoline which are derived from petroleum. For example, a combination of gasoline and ethyl alcohol sometimes called "gasohol" has been widely heralded because it lowers the amount of gasoline required to run an internal combustion engine. Of course, gasohol contains a large amount of gasoline (90%). It would, of course, be desirable to find a substitute for gasoline which does not employ any petroleum derivatives at all. The use of straight ethanol as an engine fuel has been explored. This approach, however, suffers from a number of deficiencies, one of which is that the principal source of ethanol is grain which would otherwise be directed to food products.
It would, of course, be highly desirable to utilize coal as a fuel for powering automobiles and other vehicles. One method suggested for utilizing coal as a fuel for internal combustion engines involves converting the coal to methanol. A suggested use for methanol is to add it to gasoline to make a fuel similar to gasohol. As an additive or extender for gasoline, methanol could fulfill a function similar to that of ethanol; but, adding methanol to gasoline presents problems. If even a small quantity of water gets into an automobile tank, a methanol-gasoline blend will separate. The methanol and water fall to the bottom of the tank, get into the engine and stall it.
The use of straight methanol as a fuel has been suggested. With minor modifications to the engine, such as raising the engine's compression ratio and adding a heating system for cold starts, an automobile can run on straight methanol. However, methanol produces only about half the calories per gallon as conventional gasoline. In connection with the foregoing, the heat of combustion figures for gasoline and methanol appear below:
Gasoline: 10.5 kilocalories per gram PA1 Methanol: 4.7 kilocalories per gram PA1 less than 400 P.P.M. Hydrocarbons PA1 less than 2% Carbon Monoxide) PA1 60 P.R.M. Hydrocarbons PA1 0.1% Carbon Monoxide PA1 250 P.P.M. Hydrocarbons PA1 10% Carbon Monoxide PA1 180 P.P.M. Hydrocarbons PA1 7% Carbon Monoxide PA1 100 P.P.M. Hydrocarbons PA1 2.6% Carbon Monoxide
The significance of the foregoing is that studies anticipate that the price at the plant gate for converting coal to methanol is about 55-65% of the retail price of gasoline. Thus, unless the combustion characteristics of methanol is somehow improved, it would not be competitive with gasoline as it is presently priced. It would, of course, be highly desirable to increase the combustion characteristics of methanol so that it would be economical to use methanol as a substitute for gasoline. Of course, it should also be noted that in addition to producing methanol synthetically from coal, it can also be produced from forest and farm wastes such as wood chips, garbage, plant stocks and manure.